Pretty sure I have covered this before, but it's always worth a refresh. When you choose to read more, I will include a time lapse video so you can watch me work.
First of all prep the surface that you wish to apply the decal to. Make sure there is no dirt, and you can mix 5-10% dish soap with water to create a decent surface spray. This will allow you to slide your decal a little. The solution can help you with positioning, and bubble eradication.
I have applied decals in dust bowls, and in the freezing rain. It is best to be in a climate controlled situation, but sometimes you just gotta make it work. I find that direct sunlight and hot weather is the hardest working condition, especially for large decals. The surface area can heat the vinyl and turn it into an almost fluid state. The rain isn't so bad, as long as you can sop up the water fast enough, bring a towel.
Take your decal (still attached to wax paper and application tape) and position it with painters tape. I use two long pieces dead center on the decal, and cap that with perpendicular pieces of tape. I find that doing this helps relieve some of the tension caused by the application process, and helps to prevent the decal from moving. I then peal up one side of the decal, away from the wax paper. I peal it all the way to the center point where I attached the painters tape. I then cut away the wax paper underneath. In the video you can see that I have someone holding the decal taught, so it doesn't touch the surface as I work my way out from the middle, flattening the decal as I go.
Once you have one side done you can than switch to the remaining side, and remove the painters tape altogether. If you're doing other decals than you may want to save the tape. Just peal the remaining side away from the wax paper, and work towards the center. The wax paper will fall away, and then you can flatten out the remaining side. This should all feel like déjà vu.
In this video we are doing multiple decals over a corrugated surface. When I first started doing vinyl I thought the corrugated surface would be hard, but now it is a welcomed challenge. I like to say that the corrugation actually makes it easier because the vinyl will stretch out nicely over it. Sometime flat surfaces can be more difficult because if you have a big bubble and you didn't prep, well you have nowhere to go with the extra stretched material. With a corrugated surface you have more pockets to fill with the material.
The coolest thing about these decals is that we are doing multiple colors over top of each other. They sell multi-colored vinyl but this is simple enough, and I am not sure if they sell multicolored vinyl in neon. I also use the stars to hide flaws and help balance the image onto the trailer.
Tools You Need: Xacto, Scissors, Painters Tape
Tools You Want: Picker, Squeegee
Let me know what you think! I hope this was helpful.